Abstract
Nordenstamia valenzuelae sp. nov. is described from the Pui Pui Protection Forest in central Peru. It is a shrub characterized by opposite leaves (upper ones sessile), adaxial leaf surfaces and young stem parts covered by short-stipitate, basic T-shaped, golden-yellow trichomes, and densely white lanate abaxial leaf surfaces. The new species is compared with the morphologically closest taxa and useful characters for their proper identification are provided. A dichotomous key including the Nordenstamia species with consistently opposite phyllotaxy is also presented.